Interactions of stimulus quality and semantic context on N400 in visual word recognition

The joint effects of stimulus quality and semantic context in visual word recognition were examined with event-related potential (ERP) recordings. In one-character Chinese word recognition, we manipulated stimulus quality at two degradation levels (highly vs. slightly degraded) and semantic context at two priming levels (semantically related vs. unrelated). In a prime–target–probe trial flow, ERPs were recorded to the target character which was presented in either high or slight degradation and which was preceded by either a semantically related or unrelated prime character. The target character was then followed by a probe character which was either identical to or different from the target character. Subjects were instructed to make target–probe matching judgments. The ERP results demonstrated a degradation by priming interaction, with larger N400 semantic priming effects for slightly degraded targets. Moreover, the degradation effects were observed on the P200, N250, and N400. These findings provided evidence for the cascaded model of visual word recognition such that the visual processing cascaded into the semantic stage and thus interacted on the N400 amplitude. The results were compared to an earlier study with a null ERP degradation by priming interaction. The ramifications of these results for models of visual word recognition are discussed.

Children use artifacts to infer others' shared interests

Artifacts – the objects we own, make, and choose – provide a source of rich social information. Adults use people’s artifacts to judge others’ traits, interests, and social affiliations. Here we show that 4-year-old children (N=32) infer others’ shared interests from their artifacts. When asked who had the same interests as a target character, children chose the character with a conceptually similar object to the target’s – an object used for the same activity – over a character with a perceptually similar object. When asked which person had the same arbitrary property (bedtime, birthday, or middle name), children did not systematically select either character, and most often reported that they did not know. Adults (N=32) made similar inferences, but differed in their tendency to use artifacts to infer friendships. Overall, by age 4, children show a sophisticated ability to make selective, warranted inferences about others’ interests based solely on their artifacts.

Meanings within meanings: Skilled readers activate irrelevant meanings of radicals in Chinese

Many characters in written Chinese incorporate components (radicals) that provide cues to meaning. The cues are often partial, and some are misleading because they are unrelated to the character’s meaning. Previous studies have shown that radicals influence the processing of the characters in which they occur (e.g., Feldman & Siok, 1999). We investigated whether readers automatically activate the semantics associated with a radical even when it is irrelevant to the character’s meaning, using a modified version of the Van Orden (1987) task. Fifty-one Mandarin speakers participated in the study. On each trial they were shown a reference category such as “animal” prior to seeing a target character then indicated whether the target character was a member of that category. Decisions were slower and less accurate when a target that is not a member of the target category contained a radical that is. For example, if the category is “found in the kitchen,” the answer for the target 券 (ticket) is no; however the character contains the misleading radical 刀 (knife). These patterns suggest that readers process the semantics of the radical even when it is not relevant to the meaning of the character. The results present challenges for theories in which whole characters are the units of processing in reading Chinese. They also raise questions as to whether repetitions of this experience may result in some of the irrelevant semantics influencing the meaning of the character.

Similarity between referents constrains the processing of contrastive focus during reading

Contrastive focus implies a contrast between two elements. However, it is unclear whether and how any interplay between such a contrast and similarity between potentially contrasting elements might affect focus processing. Accordingly, we report an eye movement experiment investigating this issue. The experiment used a background story to introduce eight characters whose social identities were manipulated to be similar or dissimilar. Participants first read this background story, then a series of two-sentence discourses while their eye movements were recorded. Each discourse referred to two characters from the passage who had either similar or dissimilar identities, with one (the target character) either focused using the Chinese particle zhiyou (meaning only) or unfocused. The results showed a typical focus facilitation effect, such that target character names were processed more quickly when focused than unfocused. We also observed a main effect of the similarity/dissimilarly of characters and, crucially, an interaction between this variable and focus. This interaction was due to slower processing of a post-target region when the target character was focused and the two characters had similar rather than dissimilar identities, but no such effect when the target character was unfocused. The findings suggest that establishing a contrast between referents is effortful during reading when these have similar rather than dissimilar social identities and so are more difficult to differentiate. The distinctiveness of referents in a discourse context may therefore constrain the establishment of contrastive focus during reading. We discuss these findings in relation to current theories of focus interpretation.

Comparison of the BCI Performance between the Semitransparent Face Pattern and the Traditional Face Pattern

Brain-computer interface (BCI) systems allow users to communicate with the external world by recognizing the brain activity without the assistance of the peripheral motor nervous system. P300-based BCI is one of the most common used BCI systems that can obtain high classification accuracy and information transfer rate (ITR). Face stimuli can result in large event-related potentials and improve the performance of P300-based BCI. However, previous studies on face stimuli focused mainly on the effect of various face types (i.e., face expression, face familiarity, and multifaces) on the BCI performance. Studies on the influence of face transparency differences are scarce. Therefore, we investigated the effect of semitransparent face pattern (STF-P) (the subject could see the target character when the stimuli were flashed) and traditional face pattern (F-P) (the subject could not see the target character when the stimuli were flashed) on the BCI performance from the transparency perspective. Results showed that STF-P obtained significantly higher classification accuracy and ITR than those of F-P (p < 0.05).

Research of Image Segmentation Based on Iterative Threshold

Image segmentation is the key step in image recognition,the result of segmentation affects the one of recognition directly.The article introduces the concept and detailed definition of the image segmentation. The segmentation algorithm of iterative threshold in detail. According to the intrinsic characteristics of weed images, just can use the iteration threshold segmentation method, and implements them by Matlab programme, then processes three weed images, respectively to obtain effective results , and establishes a good base for the pick-up of the target character.

Bangla Character Recognition Using Optical Joint Transform Correlation

Automatic Bangla character recognition has been a great challenge for research and development because of the huge number of characters, change of shape in a word and in conjunctive characters, and other similar reasons. An optical joint transform correlation-based technique is developed for Bangla character recognition which involves a simple architecture, but can operate at a very high speed because of optics, and offer a very high level of accuracy with negligible false alarms. The proposed correlation technique can successfully identify a target character in a given input scene by producing a single correlation peak per target at the target location. The discrimination between target and non-target correlation peaks is found to be very high even in noisy conditions. The recognition performance of the proposed technique is observed to be insensitive to the type and number of targets. Further improvement of the technique is made by incorporating a synthetic discriminant function, which is created from distorted images of the target character and hence can make the system efficiently recognize Bangla characters in different practical scenarios.

The Estimation of Precession Character Based on Multi-LOS HRRP

In this paper, we use the cone as the model of the warhead to analysis its precession character and target character, which will affect the HRRP (High Resolution Rang Profile) of the warhead. What’s more, we build a model to simulate the situation when the target is observed from multiple line-of-sight (multi-LOS) of radar. After all the research, we come up with an arithmetic that joins precession character and structure character which are based on the multi-LOS time-HRRP. This arithmetic uses all the information that received by radars simultaneously, which can improve the accuracy of the estimation. The simulation experiment indicates the effectiveness of the arithmetic.